Coal-drill



(MMM) W. BULLUGK.

GOAL DRILL.

Patented Ont. 27

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UNITED STATES WILLIAM EULLUoIt, oF oENTEALIA, PENNSYLVANIA.

PATENT OFFICE.

C O A L D R L L SPECIFICATION forming part of Letters Patent No. 462,199, dated October 27, 1891. Application tiled March 28, 1891. Serial No 386,729. (No model.)

To a/ZZ whom it may concern:

Be it known that I, WILLIAM BULLUCK, a citizen of the United States, and a resident of Centralia, in the county ot' Columbia and State of Pennsylvania, have invented certain new and useful Improvements in Coal-Drills; and I do declare the following to be a full, clear, and exact description of the invention, suchas will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters of reference marked thereon, which form a part of this specification.

Figure l of the drawings is a side view. Fig. 2 is a longitudinal sectional view. Fig. 3 is a sectional view of a modication.

This invention has relation to certain new and useful improvements in coal-drills; and it consists in the novel construction and combination of parts hereinafter described, and pointed out in the claim.

In the accompanying drawings, the letter A designates the drill-bar and wedge, which maybe of any well-known form, hung in the swing B.

C is the drill-rod, which, instead of the solid screw heretofore used, consists of a gas-pipe threaded on the outside and having an aperture large enough to permit the passage therethrough of the drill, as shown, in which it is held by means of the clamp D. The pipe C works through the clamp or guide nut C', carried by the swing B.

F is the operating-handle. By this arrangement when the rod E has been worked to the end of its screw the clamps C and I) maybe loosened and the pipe slipped back on the drill, leaving the drill in the same position and thus practically doubling its length.

In Fig. 2 I have shown a special form ot' the holding-clamp D, wherein the pipe C is shown as swelled to form the conical section C', in which are inserted the tapering corrugated clamping wedges e e. Then these are clamped against the drill, they will' effectually prevent its turning.

This improvement may be applied to nearl y it' not all of the drills of this character now in use.

Having thus described my invention, what I claim new, and desire to secure by Letters Patent, is-

The drill mechanism comprising the hollow guide C, having the swelled conical section at its lower end and the drill held. therein and clamped by clamping-wedges, said hollow guide having an external thread working in a threaded clamp-nut carried by the swing, and an operating-crank connected to the end of said guide, substantially as specified.

In testimony whereof I aflix my signature in presence of two witnesses.

WILLIAM BULLUCK. Vitnesses:

J. B. LYNCH, JAMES MADDEN. 

